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61.
Age changes affect the oral mucosa (the protective lining of the oral cavity), but few of these have been studied objectively. The aim of this study was to quantitatively analyse a number of morphometric parameters of the ageing oral mucosa. The fractal dimension of the epithelial connective tissue interface (ECTI) was estimated in 42 samples of normal buccal mucosa to correlate any changes in their irregularity to the age of the individuals. Morphometric parameters extracted from theoretical cell areas computed programatically were also analysed. Results showed no significant change in ECTI complexity associated with age; however, there was indication that epithelial cells tended to become larger and flatter with age. Interestingly, while some parameters did not show significant differences case wise, cluster analysis showed that the data clustered the cases into three main age groups: one representing the first two decades of life, another group represents adult life (21–50 years) and the last group representing the ageing population (50–90 years).  相似文献   
62.
目的:了解正常膝关节软骨分布及股骨髁承重区的软骨厚度特点,为膝关节病变早期诊断和动态观察提供依据。方法:选取100名成人志愿者,男、女各50名,年龄20—30岁,平均25.3岁,膝关节均行MRI扫描。应用MIMICS软件对图像进行处理,在矢状位窗面上测量膝关节各部位软骨最大厚度。选择膝关节正常运动时的承重区,测量承重区域软骨的最大厚度并与其他区域进行比较。基于MRI图像行膝关节软骨三维重建,观察膝关节软骨的三维形态特征。结果:膝关节各部位的最大软骨厚度如下。胫骨外侧平台3.19mm,胫骨内侧平台3.07mm,股骨外侧髁2.93mm,股骨内侧髁3.19mm,股骨滑车软骨3.57mm,髌软骨3.75mm。不同性别与左右侧之间的软骨厚度差异无统计学意义(P〉0.05)。胫股关节承重区软骨厚度大于其他区域,有统计学差异(P〈0.05)。结论:成人正常膝关节各区域软骨厚度不同,胫股关节承重区软骨厚度大于非承重区域。基于MRI可以准确地测量膝关节各部软骨的厚度及重建膝关节软骨的三维形态。  相似文献   
63.
The aim of the present study was to investigate associations between thoracic hyper- and hypokyphosis, head posture, and craniofacial morphology in young adults. Using forward bending test and spinal pantographic measurements, 31 subjects, 16 with thoracic hyper- and 15 with hypokyphosis, were selected from a population-based cohort of 430 young adults. Lateral roentgen-cephalograms were taken in natural head posture and craniofacial and postural angular measurements were calculated. Any statistically significant differences between the groups - thoracic hyperkyphosis and thoracic hypokyphosis - were analysed using Student's t test. Subjects with thoracic hyperkyphosis had a larger atlantocervical angle (At/CVT, P < 0.01) than subjects with thoracic hypokyphosis. However, head position (NSL/VER)was similar in both groups, probably owing to the visual perception control of craniovertical relation. There was no statistically significant difference in craniofacial morphology between the groups.  相似文献   
64.
目的:研究藤梨根提取物(ethanol extract from radix of actinidia chinensis,EERAC)对人大肠癌LoVo细胞增殖和凋亡的影响.方法:提取藤梨根抗癌有效活性成分(EERAC),按浓度分为4处理组(10、40、160、320mg/L)和空白对照组(0mg/L).各实验组经作用24、48、72h后,进行一般形态学和AO/EB荧光染色观察;MMT法检测细胞增殖的抑制情况;免疫组织化学(immunohistochemistry,IHC)法测定LoVo细胞中凋亡相关基因Bcl-2、Bax、Caspase-3的蛋白表达变化.结果:与空白对照组比较,一般形态学显示EERAC处理组能使细胞密度减低,增殖变慢;细胞逐渐变大,细胞间接触变松,胞浆中颗粒增多,细胞脱壁现象和周围碎片增多;荧光染色观察可见处理组细胞呈橙红色荧光,细胞核出现碎片状或固缩状的凋亡特征学形态改变,凋亡现象与EERAC的浓度呈正相关性;MTT法检测显示,EERAC处理组对LoVo细胞的最佳作用时间为72h,最大抑制率为79.48%,具有浓度和时间的依赖性(P<0.01);IHC检测结果显示EERAC作用LoVo细胞24h后,Bcl-2表达明显减弱,Bax、Caspase-3表达水平明显增高,Bcl-2/Bax比值下降,差异具有统计学意义(P<0.05),其效应与浓度相关.结论:EERAC具有明显抑制LoVo细胞增殖的作用,其机制可能与降低Bcl-2表达,上调Bax、Caspase-3的表达水平,激活线粒体凋亡途径有关.  相似文献   
65.
背景:关节镜下重建交叉韧带已得到广泛应用,关于腱骨愈合状态的研究多集中在患肢功能恢复以及愈合程度及稳定性观察方面。目的:了解韧带重建过程中各种固定方式对肌腱.骨界面愈合的影响。方法:2009年7月至2009年9月以长白二号体重100千克左右的八头成年猪的双膝关节作为实验对象进行动物实验,采用四种固定方式对腱-骨进行固定,包括纽扣接骨板悬吊固定、肌腱包裹自体松质骨方式、界面挤压螺钉固定、横穿可吸收钉固定,对手术后6周、12周时界面愈合的情况进行病理切片观察。结果:纽扣接骨板固定模式腱骨界面愈合均匀,理论抗拉力大,相反固定物对腱骨界面干扰明显的界面愈合不理想,骨纤维细胞排列不整齐,理论拉力降低,尤其表现在界面挤压螺钉方面;对于有自体松质骨植入的在腱骨愈合过程中活性骨质坏死,无促进腱骨愈合的作用。结论:在腱骨愈合过程中界面固定方式对早期愈合有不同程度的影响,悬吊固定方式腱.骨愈合界面形态学表现理想。  相似文献   
66.
This study investigated the relationship between white matter microstructure and the development of morphosyntax in a spoken narrative in typically developing children (TD) and in children with high functioning autism (HFA). Autism is characterized by language and communication impairments, yet the relationship between morphosyntactic development in spontaneous discourse contexts and neural development is not well understood in either this population or typical development. Diffusion tensor imaging (DTI) was used to assess multiple parameters of diffusivity as indicators of white matter tract integrity in language-related tracts in children between 6 and 13 years of age. Children were asked to spontaneously tell a story about at time when someone made them sad, mad, or angry. The story was evaluated for morphological accuracy and syntactic complexity. Analysis of the relationship between white matter microstructure and language performance in TD children showed that diffusivity correlated with morphosyntax production in the superior longitudinal fasciculus (SLF), a fiber tract traditionally associated with language. At the anatomical level, the HFA group showed abnormal diffusivity in the right inferior longitudinal fasciculus (ILF) relative to the TD group. Within the HFA group, children with greater white matter integrity in the right ILF displayed greater morphological accuracy during their spoken narrative. Overall, the current study shows an association between white matter structure in a traditional language pathway and narrative performance in TD children. In the autism group, associations were only found in the ILF, suggesting that during real world language use, children with HFA rely less on typical pathways and more on alternative ventral pathways that possibly mediate visual elements of language.  相似文献   
67.
Since abnormalities in distal upper limb development are among the minor physical anomalies associated with schizophrenia we attempted to determine whether patients with schizophrenia can be identified on the basis of specific morphologic and dermatoglyphic features of the hand. Photographs and prints of the hands of 38 patients with schizophrenia and those of 42 control subjects were evaluated and graded on 13 biometric parameters. Results were statistically evaluated. A combination of three of the parameters was found to have good predicting abilities to distinguish between schizophrenics and controls. Subjects having high values in these three parameters were found to have a higher propensity to be defined as schizophrenics. In order to define a simple rule for classifying subjects we chose a criterion of having a value of 3 (in a scale from 1 to 3) in at least one of these three discriminating variables. This rule yielded an overall accuracy of 81.2%. Among controls, 85.7% of subjects did not fulfill such criteria, while 14.3% were defined as false positives. Among schizophrenics 76.3% achieved this condition while 23.7% were false negatives. The technique's objectivity and ease of application could facilitate the diagnosis of this disease.  相似文献   
68.
Although it is well‐established that children with Specific Language Impairment characteristically optionally inflect forms that require tense and agreement marking, their abilities with regards to derivational suffixation are less well understood. In this paper we provide evidence from children with Grammatical‐Specific Language Impairment (G‐SLI) that derivational suffixes, unlike tense and agreement suffixes, are not omitted in elicitation tasks. We investigate two types of derivation – comparative/superlative formation and adjective‐from‐noun formation – and reveal that G‐SLI children supply these suffixes at high rates, equivalent to their language matched peers. Moreover, increasing the phonological or morphological complexity of the stimulus does not trigger suffix omission, although it results in non‐target forms that are not characteristic of typically developing children. We discuss what these results reveal about the nature of the deficit in G‐SLI within the context of three hypotheses of SLI: the Extended Optional Infinitive, Implicit Rule and Computational Grammatical Complexity Hypotheses.  相似文献   
69.
目的初步探讨消幻汤含药血清对人神经母细胞瘤细胞SH—SYSY的增殖及形态的影响。方法通过连续7d给家兔灌胃给药,制备消幻汤含药兔血清、利培酮含药免血清及空白兔血清。将上述血清作用于SH—sY5Y细胞24~72h,通过倒置显微镜观察舍药血清干预48h的SH—SY5Y细胞的形态,并且每24小时采用MTT法检测SH~SY5Y细胞的增殖情况。结果消幻汤含药血清处理48h的SH—SY5Y细胞突起较长,细胞间接触紧密,并且伸出伪足,虽表现为增殖旺盛,但消幻汤含药血清对SH—SY5Y细胞的增殖与空白血清相比,差异无统计学意义(P〉0.05),而利培酮含药血清则可显著增加sH—SY5Y的细胞数量,呈现对数增殖趋势,与其他各组比较,差异有统计学意义(P〈0.05)。结论消幻汤含药血清对SH—SY5Y细胞的正常形态有促进作用,而对SH—SY5Y细胞的正常增殖无显著干预作用,与利培酮舍药血清作用不同。  相似文献   
70.
目的分析安全置入胸椎椎弓根钉相关的椎弓根解剖形态特点,研究在探设成人胸椎椎弓根钉通道过程中需要重点探查的区域。方法使用CT三维重建图像对60位正常发育的成人胸椎椎体和15例胸椎椎弓根钉穿出椎弓根内侧壁的胸椎手术患者进行测量。测量参数包括:临界距离,安全距离,椎弓根钉通道长度,椎弓根宽度,椎弓根横向角,穿出距离。危险区域定义为安全距离和临界距离之差。结果成人不同节段胸椎的临界距离为8.69~10.53 mm,安全距离为14.53~16.16 mm,危险区域为5.10~6.41 mm。临界距离、安全距离与危险区域相对恒定。椎弓根钉通道长度为31.21~45.01 mm,椎弓根宽度为4.03~8.29 mm。椎弓根横向角从T1的27.68°逐渐减少到T12的7.82°。15枚穿出椎板腹侧皮质或者椎弓根内侧皮质的椎弓根钉的穿出距离为(12.68±1.12)mm,所有的穿出距离均介于临界距离和安全距离之间。结论正确认识成人胸椎的临界距离、安全距离和危险区域有助于安全置入胸椎椎弓根钉。  相似文献   
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